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11.
T Hasegawa S Izumi S Kurihara Y Ishizuka Y Ito A Takechi M Tsuchiya 《Acta cytologica》1985,29(3):363-366
In a high-volume cytology laboratory in the metropolitan Tokyo area, the incidence of cytologically diagnosed herpes infection in cervical scraping smears of the female genital tract was studied according to the year-by-year changes, age distribution, seasonal variation and types of cytologic alteration. The overall incidence over the 12 years studied was 0.007% (87 cases among 1,230,773 examined). The incidence varied from 0.003% to 0.005% in the early 1970s (except for 1973) and increased to 0.011% in the last three years (1980 to 1982). A large increase was noted in younger age groups in comparison with middle and older age groups. There was a tendency for the infection rate to be higher in the spring (0.011%) and lower in the fall (0.005%). Multinucleation and a ground-glass appearance were observed in the infected cells in almost every case while eosinophilic inclusion bodies were found in 20.7% of the cases. 相似文献
12.
Akio Horie Joji Haratake Isamu Tanaka Yasushi kodama Kemzaburo Tsuchiya 《Biological trace element research》1985,7(4):223-239
A special exposure system was used for the inhalation of nickel oxide (NiO) aerosol by Wistar male rats. The median aerodynamic diameter and the geometric standard deviation were 1.2 μm and 2.2, respectively. A histopathological study of the rats was performed immediately, and at intervals of 12 and 20 mo after a 1-mo expsoure to NiO. Electron microscopy showed that localization of NiO particles was restricted to the lungs and that each particle had been engulfed by the alveolar macrophages. Type II pneumocytes and nonciliated bronchiolar epithelial cells (Clara cells), as well as numerous tubular myelin (surfactant) in the alveoli were prominent. In rats dissected after 12 mo, clusters of NiO particles were still present within the terminal bronchioli, alveolar walls, and lysosomes of the alveolar macrophages. Pools of tubular myelin were observed in the peribron-chial lymphatics. The Clara cells, which project into the lumen of bronchioli, showed active secretion and were filled with smooth en-doplasmic reticulum (SER) in the apical cytoplasm. In the experimental group sacrificed after 20 mo, one rat had papillary adenocarcinoma and two rats showed adenomatosis in the peripheral portion of the lung, but none in the upper respiratory tract. 相似文献
13.
Y Kubota Y Watanabe H Otsuka T Tamiya T Tsuchiya J J Matsumoto 《Comp. Biochem. Physiol. C, Comp. Pharmacol. Toxicol.》1985,82(2):345-348
The antibacterial factor from the body surface of the African giant snail, Achatina fulica Férussac, was isolated by DEAE-Toyopearl 650M ion exchange chromatography. The isolated preparation exhibited highly positive antibacterial activity both for the Gram-positive bacteria, Bacillus subtilis and Staphylococcus aureus and for the Gram-negative bacteria, Escherichia coli and Pseudomonas aeruginosa, but it lost such activity when heated at 75 degrees C for 5 min. The antibacterial factor of the snail mucus was a glycoprotein whose molecular weight (MW) was about 160,000. It was composed of two subunits of MW 70,000-80,000. 相似文献
14.
M. Nakamura M. Oda Y. Yonei N. Tsukada H. Komatsu K. Kaneko M. Tsuchiya 《Histochemistry and cell biology》1985,83(6):479-487
Summary The muscarinic cholinergic innervation of the rat gastric mucosa was investigated by localizing the muscarinic receptors using a tritiated muscarinic antagonist, pirenzepine. Radioautography was performed by freeze drying stomach tissue, which was then embedded in Epon and wet sectioned with ethylene glycol, and dry mounting on emulsion film by the wire-loop method to prevent loss of the labelled substance during fixation and the radioautographic procedure. Light and electron microscopy showed that the specific pirenzepine-binding sites were localized predominantly on parietal cells, chief cells and perivascular plexuses. Analysis of the grain distribution on parietal cells revealed that the silver grains corresponding to the pirenzepine-binding sites were mainly on the basolateral plasma membrane. On the other hand, the surface mucous or mucous neck cells had few pirenzepine-binding sites. 相似文献
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H Sakurai M Nakai T Miki K Tsuchiya J Takada R Matsushita 《Biochemical and biophysical research communications》1992,189(2):1090-1095
Vanadyl ion (+4 oxidation state) has been shown to be an effective agent for chemoprotection of cancers in animals. For understanding the mechanism, distribution of vanadium was studied. More vanadium was found to accumulate in the nuclei of the liver of rats when it was given as vanadyl sulfate than when it was given as sodium vanadate (+5 oxidation state). The reactivity of vanadyl ion with DNA was investigated by the DNA cleavage technique and the reaction mechanism by ESR spectroscopy. Incubation of double-strand DNA with vanadyl ion and hydrogen peroxide resulted in marked concentration- and pH-dependent DNA cleavage. Studies by the ESR spin-trap method demonstrated that hydroxyl radicals are generated during the reactions of vanadyl ion with hydrogen peroxide. Thus the antineoplastic action of vanadyl ion is proposed to be due to DNA cleavage by hydroxyl radicals generated in the cells. 相似文献
19.
M. Sunairi H. Tsuchiya T. Tsuchiya Y. Omura Y. Koyanagi M. Ozawa N. Iwabuchi H. Murooka M. Nakajima 《Journal of applied microbiology》1995,79(2):225-229
Anaaki disease causes severe damage to the red algae Porphyra yezoensis from which the Japanese traditional food 'nori'is produced. The causative agent of anaaki disease was isolated by several repeats of single-colony isolation and infection experiments, and was identified as Flavobacterium sp. LAD-1. The bacterium showed hydrolytic activity toward porphyran but not toward other polysaccharides composing the thallus of Porphyra , such as β-1,3-xylan or β-1,4-mannan. The bacterium also showed β-D-galactosidase activity. 相似文献
20.
Noriko Katayama Emi Iwata Hiroaki Sakurai Tomofusa Tsuchiya Masaaki Tsuda 《Journal of neurochemistry》1993,60(3):902-907
Abstract: Administration of carbachol, noradrenaline, and bradykinin induced Egr-1 mRNA expression within 1 h in mouse neuroblastoma × rat gliomahybrid NG108–15 cells. With specific receptor antagonists, the Egr-1 inductions by carbachol and noradrenaline were shown to be mediated via cholinergic muscarinic and α2 -adrenergic receptors, respectively. At their saturation levels for Egr-1 induction, the two agonists had additive effects when added together, but no prolongation of the effect on Egr-1 induction was observed. Addition of carbachol or noradrenaline 6 h after primary stimulation with carbachol or noradrenaline did not result in secondary Egr-1 induction, probably because of receptor desensitization. On the other hand, bradykinin consistently had an additive effect on Egr-1 induction, irrespective of the time of its addition, suggesting that the signal pathways for Egr-1 induction by carbachol or noradrenaline and by bradykinin are different. Treatment of cells with pertussis toxin or cholera toxin strongly inhibited Egr-1 induction by carbachol or noradrenaline but only partially inhibited the induction by bradykinin. Thus, the signals transduced in NG108–15 cells by different neurotransmitter receptors appear to have different effects on Egr-1 induction, depending on the times of stimulation and the combinations of receptors stimulated. 相似文献